The present invention relates to a plate blender for use in the blending of particulate and granular solid materials. More particularly, the present invention relates to a plate blender which in one embodiment includes a cylindrical tank having a plurality of vertical, radially extending baffles installed therein, and with a series of vertically spaced windows in at least some of the baffles. The plate blender of the present invention may be advantageously employed in the blending of flowable particulate solid materials such as plastic pellets and powders.
Previous blending apparatus for the blending of various types of grains and powders are described, for example, in the following U.S. Pat. Nos.: 2,270,847 to Hyman; 2,455,572 to Evans; 3,145,975 to Towns; 3,275,303 to Goins; 3,423,076 to Jacobs et al.; 4,207,009 to Glocker; and 4,412,748 to Wohnhas et al.
By the present invention, there is provided an improved mixing and blending apparatus for particulate material in which a plurality of window openings are positioned in vertical, radially extending baffles to create a gravity flow sequence which will provide a blended material at the outlet. The window arrangement and spacing is determined from the material inlet conditions which define the time/volume relationship for the parameters to be blended. This window/baffle arrangement results in the material to be blended being allowed to flow successively from one blending zone to the next around the circumference of the vessel and with the location and number of windows providing for consecutive layers of material throughout the zones.